A bookmarklet to use a portion of the current URL in a new URL

Question

I'm wanting to make a bookmarklet that would change a webpage from http://user.tumblr.com/post/123456789 to http://user.tumblr.com/liked/by/user with just a click. I'm usually alright at frankensteining code together, and I've been looking at the Tumblr manual reblog button that uses "window.location" along with Bookmarklet to edit current URL and Replace end characters of current URL with bookmarklet I can't see anything useable that would extract a subdomain into a variable and then place it in a new URL. I did stumble across this code: ^http://([^.]+)\.domain\.com But I have no idea what that means or how to use it. JavaScript questions and answers, JavaScript questions pdf, JavaScript question bank, JavaScript questions and answers pdf, mcq on JavaScript pdf, JavaScript questions and solutions, JavaScript mcq Test , Interview JavaScript questions, JavaScript Questions for Interview, JavaScript MCQ (Multiple Choice Questions)

Answer 1

Not sure if this is what your looking for, but I use as I have multiple instances of my site and what bookmarks to keep me in the same instance regardless of port or protocol. New Tab javascript:(function(){window.open(location.protocol+'//'+location.hostname+':'+location.port+'/liked/by/user')})(); Current Tab javascript:(function(){window.location.assign(location.protocol+'//'+location.hostname+':'+location.port+'/liked/by/user')})(); EDIT: Forgot to put code blocks